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Add data-parsley-cantmin="2" attribute to the select2 field
Initialize the ParsleyConfig object as following
window.ParsleyConfig = { validators: { cantmin: { fn: function (value, requirement) { //return value !== requirement; if ($("#campoprofesionales").val()) if($("#campoprofesionales").val().length > 1) {return true} else {return false} }, priority: 32 } }, i18n: { en: { cantmin: 'You have to select at least %s items from the list' }, es: { cantmin: 'Tiene que seleccionar al menos %s items de la lista' } } };